Display device

ABSTRACT

An organic electroluminescent device with a touch sensor including: a first substrate; a second substrate arranged opposite to the first substrate; an organic EL element layer arranged above the first substrate; a first sealing film arranged toward the second substrate of the organic EL element layer, covering the organic EL element layer, and including a first inorganic layer; plural first detection electrodes extending in one direction, and arranged in parallel toward the second substrate of the first sealing film; a second sealing film arranged toward the second substrate of the first detection electrodes, and including a second inorganic layer; plural second detection electrodes extending in another direction different from the one direction, and arranged in parallel toward the second substrate of the second sealing film; and a touch sensor control unit control ling a potential to detect a touch with a display surface.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority from Japanese patent applicationJP2013-179505 filed on Aug. 30, 2013, the content of which is herebyincorporated by reference into this application.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a display device.

2. Description of the Related Art

JP-2012-156140 A discloses an organic light emitting display deviceincluding: a substrate; a display part that is formed on the substrate;a sealing substrate having a surface that faces the substrate; acapacitance type touch unit having plural first sensors that are formedon any surface of the sealing substrate to be aligned along a firstdirection, and plural second sensors that are formed to be aligned in asecond direction intersecting the first direction; and an insulatinglayer that is formed on at least a part of the first sensor and thesecond sensor, in which the first sensors and the second sensors areformed on any identical surface of the sealing substrate, the pluralfirst sensors and the plural second sensors are made of ITO, formed onthe surface of the sealing substrate, sense touch to generate anelectric signal, and output electric signals generated in each of theplural first sensors and the plural second sensors of the touch unitthrough data lines, the display part has thin film transistors formed onthe substrate, and organic light emitting elements coupled with the thinfilm transistors, each of the organic light emitting elements has acounter electrode, a pixel electrode, and an intermediate layer formedbetween the counter electrode and the pixel electrode, the pixelelectrode comes in contact with the thin film transistor, theintermediate layer comes in contact with at least a part of the pixelelectrode, the counter electrode comes in contact with at least a partof the intermediate layer, the touch unit is formed directly on onesurface of the sealing substrate, and the display part is formeddirectly on one surface of the substrate.

Also, JP 2008-216543 A discloses organic electroluminescent devicehaving an input function, including; an element substrate having a lightemitting layer held between a pair of electrodes, a sealing substratethat seals the element substrate; a first detection electrode that isdisposed on an inner surface side of the sealing substrate; a seconddetection electrode that is disposed on an outer surface side of thesealing substrate, and has a detection axis different from that of thefirst detection electrode, a dielectric film that is laminated on thesecond detection electrode; and detection means for detecting aformation position of a capacitance formed between the first and seconddetection electrodes through the dielectric film.

SUMMARY OF THE INVENTION

As a method giving an input function on a display screen of the organicEL device, a method of appending a touch panel (touch sensor) to asurface of a display screen, and conducting operation by a finger or apen, as disclosed in, for example, JP 2012-156140 A, and JP 2008-216543A is realized.

However, the display device with the touch sensor in which the touchpanel is adhered to the surface of the display screen as another member,or provides the touch sensor function in a part of the counter substrateof the display device as disclosed JP 2012-156140 A and JP 2008-216543 Ais large in the thickness of the device per se, and hardly satisfies ademand for thinning electronic devices in recent years.

In view of the above problem, the present inventors have earnestlystudied the provision of a display device with a touch sensor which isthinner than the display device with the touch sensor in which the touchpanel is adhered to the surface of the display screen as another member,or provides the touch sensor function in a part of the counter substrateof the display device.

An object of the present invention is to provide an organicelectroluminescent device with a touch sensor which is thinner than thedisplay device with the touch sensor in which the touch panel is adheredto the surface of the display screen as another member, or provides thetouch sensor function in a part of the counter substrate of the displaydevice.

Also, the above and other objects, and novel features of the presentinvention will become apparent from the description of the presentspecification, and the attached drawings.

In order to solve the above problem, according to the present invention,there is provided a display device, including: a first substrate inwhich pixels each having a thin-film transistor are arranged in a matrixon an insulating surface; a second substrate that is arranged oppositeto the first substrate; an organic EL element layer that is arrangedabove the first substrate and between the first substrate and the secondsubstrate, and emits light under control by a circuit including the thinfilm transistor; a first sealing film which is arranged toward thesecond substrate of the organic EL element layer, covers the organic ELelement layer, and includes at least a first inorganic layer made ofinorganic material; a plurality of first detection electrodes thatextend in one direction, and are arranged in parallel toward the secondsubstrate of the first sealing film; a second sealing film that isarranged toward the second substrate of the first detection electrodes,and includes at least a second inorganic layer made of an inorganicmaterial; a plurality of second detection electrodes that extend inanother direction different from the one direction, and are arranged inparallel toward the second substrate of the second sealing film; and atouch sensor control unit that controls a potential of any one of thefirst detection electrodes and the second detection electrodes, anddetects an electric change generated in the other detection electrodesto detect a touch with a display surface.

Also, each of the first detection electrodes and the second detectionelectrodes may have a shape having continuous rectangles (stripes)and/or continuous rhombs (diamonds). Also, each of the first detectionelectrodes and the second detection electrodes may be formed through anyone of a sputtering method and a printing method.

Also, the first sealing film may have a planarizing layer made of anorganic material toward the second substrate of the first inorganiclayer.

Also, the planarizing layer may have a thickness of 1 to 100 μm. Also, aconnection terminal for connection with the touch sensor control, unit,and a connection terminal for connection with an organic EL elementcontrol unit for controlling the light emission of the organic ELelement layer may be formed in the same plane of the first substrate.

According to the present invention, there is provided an organicelectroluminescent device with a touch sensor which is thinner than thedisplay device with the touch sensor in which the touch panel is adheredto the surface of the display screen as another member, or provides thetouch sensor function in a part of the counter substrate of the displaydevice.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of an organic electroluminescentdevice with a touch sensor according to a first embodiment of thepresent invention;

FIG. 2 is an enlarged diagram illustrating an A portion in FIG. 1, whichis a perspective view schematically illustrating an arrangement ofdetection electrodes included in the organic electroluminescent devicewith a touch sensor according to the first embodiment of the presentinvention;

FIG. 3 is a plan view schematically illustrating the arrangement of thedetection electrodes included in the organic electroluminescent devicewith a touch sensor according to the first embodiment of the presentinvention;

FIG. 4A is a cross-sectional view of the organic electroluminescentdevice with a touch sensor according to the first embodiment of thepresent invention;

FIG. 4B is a cross-sectional view of an organic electroluminescentdevice with a touch sensor according to a second embodiment of thepresent invention;

FIG. 5A is a schematic cross-sectional view illustrating a neighborhoodof a part taken along a line V-V in FIG. 3;

FIG. 5B is a cross-sectional view illustrating another example of aneighborhood of a connection terminal portion in a display deviceaccording to the present invention;

FIG. 6A is a plan view schematically illustrating an arrangement ofdetection electrodes included in an organic electroluminescent devicewith a touch sensor according to another embodiment of the presentinvention; and

FIG. 6B is a schematic cross-sectional view of a neighborhood of a parttaken along a line VI-VI in FIG. 6A.

DETAILED DESCRIPTION OF THE INVENTION First Embodiment

According to the first embodiment of the present invention, there isprovided a display device, including: a first substrate in which pixelseach having a thin-film transistor are arranged in a matrix on aninsulating substrate; a second substrate that is arranged opposite tothe first substrate; an organic EL element layer that is arranged on thefirst substrate and between the first substrate and the secondsubstrate, and emits light under control by a circuit including the thinfilm transistor; a first sealing film which is arranged on a side of theorganic EL element layer opposite to the second substrate side, andcovers the organic EL element layer; a plurality of first detect ionelectrodes that extend in one direction, and are arranged in parallel ina partial area on a side of the first sealing film opposite to thesecond substrate; a second sealing film that is arranged to coveranother area that is an outside of the partial area in which the firstdetection electrodes are arranged, and a side of the first detectionelectrodes opposite to the second substrate; a plurality of seconddetection electrodes that extend in another direction different from theone direction, and are arranged in parallel in a partial area on a sideof the second sealing film opposite to the second substrate; and a touchsensor control unit that controls a potential of any one of the firstdetection electrodes and the second detection electrodes, and detects anelectric change generated in the other detection electrodes to detect atouch with a display surface.

Hereinafter, a display device according to an embodiment of the presentinvention will be described with reference to the accompanying drawings.FIG. 1 is an exploded perspective view of an organic electroluminescentdevice with a touch sensor 10 according to a first embodiment of thepresent invention.

As illustrated in FIG. 1, the organic electroluminescent device with atouch sensor 10 according to the first embodiment of the presentinvention includes a first substrate 100 and a second substrate 600. Theorganic electroluminescent device with a touch sensor 10 according tothe first embodiment of the present invention displays an image on adisplay surface 30, and incorporates a touch sensor that detects that afinger touches any position of the display surface 30 thereinto.

A first substrate 100 included the organic electroluminescent devicewith a touch sensor 10 according to the first embodiment of the presentinvention is omitted from FIG. 1, but has a structure in which pixelseach having a thin film transistor are arranged in a matrix on aninsulating substrate. In this example, the insulating substrate maybemade of, for example, glass, plastic (polycarbonate, polyethyleneterephthalate, polyimide, polyacrylate, etc.).

Also, the first substrate 100 included in the organic electroluminescentdevice with a touch sensor 10 according so the first embodiment of thepresent invention maybe made of, for example, a light transmissivematerial. In this example, as the insulating substrate configuring thefirst substrate 100, the light transmissive material may be glass,plastic (polycarbonate, polyethylene terephthalate, polyimide,polyacrylate, etc.). Also, as wirings and electrodes configuring thefirst substrate 100, the light transmissive material may be ITO or IZO.Also, the light transmissive material is not limited to the aboveexamples.

Also, the first substrate 100 on which the circuits each using the thinfilm transistor are arranged is also called “a TFT (thin filmtransistor) substrate. In this example, the thin film transistor mayinclude a semiconductor film made of polysilicon, a gate insulating filmthat covers the semiconductor film, a gate electrode that is arrangedabove the semiconductor film through the gate insulating film, and asource electrode and a drain electrode that penetrate through the gateinsulating film, and are electrically connected to the semiconductorfilm. Also, as illustrated in FIG. 1, a driver circuit 20 for drivingthe circuits each using the thin film transistor which are arranged onthe first substrate 100 may be arranged on the first substrate 100.

Also, the second substrate 600 included in the organicelectroluminescent device with a touch sensor 10 according to the firstembodiment of the present invention may be configured by a color filtersubstrate having a color filter that transmits a light having a givenwavelength region among lights emitted from organic EL elements (referto FIGS. 2 and 4A) arranged on the first substrate. The second substrate600 which is the color filter substrate will be described in detaillater.

FIG. 2 is an enlarged diagram illustrating an A portion in FIG. 1, whichis a perspective view schematically illustrating an arrangement ofdetection electrodes included in the organic electroluminescent devicewith a touch sensor 10 according to the first embodiment of the presentinvention.

As illustrated in FIG. 2, the organic electroluminescent device with atouch sensor 10 according to the first embodiment of the presentinvention includes a laminated structure in which a first substrate 100having the circuits each using the thin film transistor, an organic ELelement layer 200, a first sealing film 300, first detection electrodes410 that extend in an X-direction, a second sealing film 500, and seconddetection electrodes 420 that extend in a Y-direction are laminated oneach other in the stated order. Although parts of the first detectionelectrodes 410 and the second detection electrodes 420 are illustratedin FIG. 2, the plural first detection electrodes 410 and the pluralsecond detection electrodes 420 are arranged in rows over the overalldisplay surface 30.

Also, as illustrated in FIG. 2, the first detection electrodes 410 arearranged in a part of an area of the first sealing film 300 opposite toa side that comes in contact with the organic EL element layer 200.Also, the first detection electrodes 410, and the other portion of thefirst sealing film 300 in which the first detection electrodes 410 arenot arranged on the first sealing film 300 are covered with the secondsealing film 500. The second detection electrodes 420 are arranged in apartial area of the surface of the second sealing film 500.

The first detection electrodes 410 extending in the X-direction, and thesecond detection electrodes 420 extending in the Y-direction in FIG. 2configure a capacitance type projection touch sensor 400. Thecapacitance type projection touch sensor will be described below.

Two kinds of a capacitance surface type and a capacitance projectiontype have been known as the capacitance type touch panel. Both of thecapacitance surface type and the capacitance projection type aredesigned to detect a position at which a fingertip touches whilecapturing a change in the capacitance between the fingertip and thedetection electrode. The touch sensor of the capacitance surface typedetects the capacitance with the configuration small in the number ofdetection terminals such as a solid electrode film and electrodeterminals of four corners. On the other hand, the touch sensor of thecapacitance projection type employs a multi-point detection system forenhancing the detection sensitivity, and therefore employs a complicatedconfiguration in which a plurality of first detection electrodes 410extending in the X-direction sterically intersect with a plurality ofsecond detection electrodes 420 extending in the Y-direction.

An arrangement relationship between the first detection electrodes 410and the second detection electrodes 420 will be described in moredetail. FIG. 3 is a plan view schematically illustrating the arrangementof the detection electrodes included in the organic electroluminescentdevice with a touch sensor 10 according to the first embodiment of thepresent invention.

As illustrated in FIG. 3, the first detection electrodes 410 and thesecond detection electrodes 420 are configured so that the rectangles(stripes) and/or the rhombi (diamonds) are aligned in lines to provideelectrodes extending in the X-direction and the Y-direction,respectively. As compared with a solid electrode employed in thecapacitance surface type, although the shape is complicated, thedetection sensitivity of the touch sensor 400 is improved with theapplication of the detection electrodes having the shape in which therectangles (stripes) and/or the rhombi (diamonds) are continuouslyarranged as described above. Therefore, this shape is preferable.

Also, the first detection electrodes 410 and the second detectionelectrodes 420 may be configured with the inclusion of main bodyportions 411 and 421 having the shape of the rectangles (stripes) and/orthe rhombi (diamonds), and connection portions 412 and 422 that connectthe main body portions 411 and 421 to the adjacent other main bodyportions 411 and 421.

Also, as illustrated in FIG. 3, lines led from the first detectionelectrodes 410 and the second detection electrodes 420 are connected toan external touch sensor control unit 50 through a flexible printedcircuit board (FPC) 800A connected to a connection terminal 450 formedon the first substrate 100.

Also, one end of the first substrate 100 in the organicelectroluminescent device with a touch sensor 10 according to the firstembodiment of the present invention is equipped with a connectionterminal 250 for driving the organic EL element layer 200. The one endof the first substrate 100 is connected to an external organic ELelement control unit (not shown) through a flexible printed circuitboard (FPC) 800B connected to the connection terminal 250.

In the organic electroluminescent device with a touch sensor 10according to the first embodiment of the present invention, therespective connection terminals 450 and 250 connected with the touchsensor control unit 50 and the organic EL element control unit can bedisposed on the first substrate 100 of the same plane. Although will bedescribed later, the connection terminal 250 for driving the organic ELelement layer 200 may coexist with the connection terminal 450 for touchsensor control provided on the first substrate 100. Also, a method ofconnecting the connection terminal portions will be described in moredetail later.

Subsequently, the organic EL element layer 200 will be described. FIG.4A is a cross-sectional view of the organic electroluminescent devicewith a touch sensor 10 according to the first embodiment of the presentinvention.

As illustrated in FIG. 4A, the organic EL element layer 200 includinganodes 210, a cathode 230, and a light emitting layer 220 held betweenthe anodes 210 and the cathode 230 is disposed on the first substrate100.

Also, sealing films 300 and 500 that protect the organic EL elementlayer 200 are formed on the organic EL element layer 200, and therespective touch sensors 400 are disposed on the sealing films 300 and500. That is, the organic EL element layer 200 and the touch sensor 400are disposed on the first substrate 100.

Hereinafter, a description will be given of the organic EL element layer200 included in the organic electroluminescent device with a touchsensor 10 according to the first embodiment of the present invention.The organic EL element layer 200 included in the organicelectroluminescent device with a touch sensor 10 according to the firstembodiment of the present invention has the anodes 210, the cathode 230,and the light emitting layer 220 held between the anodes 210 and thecathode 230, and is disposed on the above-described first substrate 100.

The anodes 210 and the cathode 230 in this embodiment may be each formedof a conductive film made of a transparent metal such as ITO or IZO.Each of the anodes 210 included in the organic EL element layer 200 issupplied with a current through the thin film transistor disposed on thefirst substrate 100. The current supplied to the anode 210 flows intothe cathode 230 through the light emitting layer 220. The light emittinglayer 220 held between the anode 210 and the cathode 230 emits light byrecoupling electrons from the cathode 230 with holes from the anode 210.The external is irradiated with the emitted light.

Also, the cathode 230 in this embodiment is formed of a solid electrodeformed over the substantially overall surface of the display surface 30of the organic electroluminescent device with a touch sensor 10. Thesolid electrode is formed over the overall surface of a given area (inthis embodiment, the display surface 30 of the organicelectroluminescent device with a touch sensor 10). For that reason, evenif a disconnection is slightly generated due to an uneven state of thesurface, the function of the electrodes is not completely impaired.

A side of the organic EL element layer 200 opposite to the firstsubstrate 100 side is equipped with the first sealing film 300. That is,a side, which faces the second substrate 600, of the cathode 230 locatedin the uppermost surface of the organic EL element layer 200 is providedwith the first sealing film 300.

Also, as illustrated in FIG. 4A, banks 240 are formed on ends of therespective anodes 210 included in the organic EL element layer 200 so asto cover the ends thereof. The banks 240 cover the ends of the anodes210 separated in the respective pixels to perform a function of definingthe light emitting areas. Hence, as illustrated in FIG. 4A, the banks240 are disposed at positions corresponding to a black matrix 610provided on the color filter substrate (second substrate 600).

Also, the respective banks 240 cover the steps of the anode 210 endsformed on the first substrate 100 to perform a function of preventingshort circuit between the anodes 210 and the cathode 230, which iscaused by the disconnection of the light emitting layer 220 in theorganic EL element layer 200. For that reason, as illustrated in FIG.4A, the banks 240 are each formed to have a smooth curve surface.

For that reason, referring to FIG. 4A, the cathode 230, which is thesolid electrode formed in the uppermost surface of the organic ELelement layer 200, is formed with smooth unevenness following the shapeof the banks 240. A surface of the first sealing film 300 disposed on aside of the organic EL element layer 200 opposite to the first substrate100 side is also formed with unevenness following the surface shape ofthe cathode 230 which is the solid electrode formed in the uppermostsurface of the organic EL element layer 200.

In this example, the first sealing film 300 is disposed for protectingthe organic EL element layer 200 from moisture and oxygen from theexternal. Therefore, a material of the first sealing film 300 isselected taking water permeability and air permeability into account.

In this embodiment, the first sealing film 300 is formed of a firstinorganic layer made of an inorganic material. Also, the first inorganiclayer may be made of a compound selected from a compound groupconsisting of SiN, SiO₂, P₂O₅.SiO₂ (PSG), Al₂O₃, PbO.SiO₂, Si₃Na₄, SiON,and PbO.B₂O₃. It is preferable that the first sealing film 300 is madeof SiN among those components. Also, the first sealing film 300 may beformed through, for example, CVD. The material and the forming method ofthe first sealing film 300 are not limited to those described above.

A thickness of the first sealing film 300 may be set to 0.5 to 5 μm.When the thickness of the first sealing film 300 may be set to 0.5 to 5μm, the effect of protecting the organic EL element layer 200 isenhanced, which is preferable.

Because the first detection electrodes 410 formed on the first sealingfilm 300 configures the capacitance type projection touch sensor 400,the first detection electrodes 410 have a complicated shape such that,for example, rectangles (stripes) and/or the rhombi (diamonds) arealigned in lines as described above. For that reason, the firstdetection electrodes 410 become in an open state when the disconnectionis generated unlike the solid electrode, and the function of the touchsensor 400 may be completely impaired. Therefore, the surface of thefirst; sealing film 300 is required to be flatter so that the firstdetection electrodes 410 are not disconnected.

Also, in particular, places in which the banks 240 are formed increasemore as the organic electroluminescent display unit provided in theorganic electroluminescent device with a touch sensor 10 becomes higherdefinition. As a result, the unevenness is liable to be more formed.

Also, the second sealing film 500 is provided for protecting theorganic. EL element layer 200 from moisture or oxygen from the externalas in the first sealing film 300. Therefore, a material of the secondsealing film 500 is selected taking water permeability and airpermeability into account.

The second sealing film 500 according to this embodiment is formed of asecond inorganic layer made of an inorganic material. Also, the secondinorganic layer may be made of a compound selected from a compound groupconsisting of SiN, SiO₂, P₂O₅.SiO₂ (PSG), Al₂O₃, PbO.SiO₂, Si₃Na₄, SiON,and PbO.B₂O₃. The second sealing film 500 is made of an organicmaterial, but may be made of, for example, polyimide resin and/orderivative thereof. It is preferable that the first sealing film 300 ismade of SiN among those components. Also, the second sealing film 500may be formed through, for example, CVD. The material and the formingmethod of the second sealing film 500 are not limited to those describedabove.

Also, a thickness of the second sealing film 500 may be set to 0.5 to 5μm. When the thickness of the second sealing film 500 may be set to 0.5to 5 μm, the effect of protecting the organic EL element layer 200 isenhanced, which is preferable.

The second detection electrodes 420 formed on the second sealing film500 have a complicated shape such that, for example, rectangles(stripes) and/or the rhombi (diamonds) are (continuously) aligned inlines as described above. For that reason, it is preferable that thesurface of the second sealing film 500 on which the second detectionelectrodes 420 are formed is flat. This is because it is conceivablethat the second detection electrodes 420 are disconnected by theunevenness of the surface of the second sealing film 500.

Also, the respective thicknesses of the first detection electrodes 410and the second detection electrodes 420 may be set to 10 to 100 μm. Whenthe respective thicknesses of the first detection electrodes 410 and thesecond detection electrodes 420 may be set to 10 to 100 μm, a sheetresistance can be reduced, which is preferable.

Also, the first detection electrodes 410 and the second detectionelectrodes 420 included in the organic electroluminescent device with atouch sensor 10 according to the first embodiment of the presentinvention may be formed through any one of a mask sputtering method anda printing method.

The organic electroluminescent device with a touch sensor 10 accordingto the first embodiment of the present invention incorporates thecapacitance projection type touch panel for the purpose of enhancing thedetection sensitivity. In order to realize the touch panel, there is aneed to pattern the complicated shape illustrated in FIG. 3. Also, inthe organic electroluminescent device with a touch sensor 10 accordingto the present invention, the organic EL element layer 200 and the touchsensor 400 are physically located at a short distance as illustrated inFIG. 4A in response to a request for thinning. Taking the above intoaccount, it is preferable to employ a method in which the touch sensor400 is formed preferably without using moisture and oxygen because theorganic EL element layer 200 hate moisture and oxygen.

For example, the method of forming the detection electrodes troughetching is not preferable in the formation of the first detectionelectrodes 410 and the second detection electrodes 420 in the organicelectroluminescent vice with a touch sensor 10 according to the firstembodiment of the present invention because the method uses a largeamount of waters for washing an etchant. Therefore, it is preferablethat the first detection electrodes 410 and the second detectionelectrodes 420 included in the organic electroluminescent device with atouch sensor 10 according to the first embodiment of the presentinvention are each formed through any one of the sputtering method andthe printing method. In the present specification, the printing methodis, for example, an inkjet method or a letterpress printing method.

Also, when the first detection electrodes 410 and/or the seconddetection electrodes 420 are formed through the mask sputtering method,if there is no space between the mask and the substrate, an influence ofscratch or foreign matter is conceivable For that reason, it ispreferable that a given space is created between the mask and thesubstrate to form the first detection electrodes 410 and/or the seconddetection electrodes 420. When the given space is created between themask and the substrate to form the first detection electrodes 410 and/orthe second detection electrodes 420, the ends of the first detectionelectrodes 410 d/or the second detection electrodes 420 are tapered.Therefore, the ends of the first detection electrodes 410 and/or thesecond detection electrodes 420 may be tapered.

Also, the first detection electrodes 410 and the second detectionelectrodes 420 may be each made of a transparent metal such as ITO orIZO, or a metal mesh, silver nanofibers, carbon nanofibers, or graphene.

The color filter substrate which is the second substrate 600 accordingto this embodiment may be of a structure in which three areas (620R,620G, 620B) partitioned by RGB are formed on a transparent substrate 630made of glass or resin. Also, a filling layer 700 made of, for example,an organic resin may be disposed between the second substrate 600 andthe second detection electrodes 420.

As compared with the organic electroluminescent device having no touchsensor, the organic electroluminescent device with a touch sensoraccording to the first embodiment as described above can be realized byonly an increase in the thickness of a sealing film structure includingthe first and second detection electrodes substantially configuring thetouch sensor, and fulfills the request for thinning.

Also, a description will be given of a method of connecting theconnection terminal portions in detail below. FIG. 5A is a schematiccross-sectional view illustrating a neighborhood of a part taken along aline V-V in FIG. 3. As illustrated in FIG. 5A, the connection terminal450 of the touch sensor 400, and the connection terminal 250 of theorganic EL element layer 200 provided in the organic electroluminescentdevice with a touch sensor 10 are formed on the same substrate (on thefirst substrate 200).

As illustrated in FIG. 5A, the first sealing film 300 and the secondsealing film 500 are removed on ends thereof in stages. With thisconfiguration, one end of the first detection electrodes 410 and one endof the second detection electrodes 420 are exposed as the connectionterminal 450 of the touch sensor 400. That is, the connection terminal450 of the touch sensor 400 is configured by one end of the firstdetection electrodes 410, and one end of the second detection electrodes420.

A flexible printed circuit board (FPC) 800A connected to the connectionterminal 450 of the touch sensor 400 is connected to one end of thefirst detection electrodes 410, and one end of the second detect ionelectrodes 420. Also, the connection terminal 250 of the organic ELelement layer 200 is connected to another flexible printed circuit board(FPC) 800B different from the flexible printed circuit board (FPC) 800Aconnected to the connection terminal 450 of the touch sensor 400.

FIG. 5B is a cross-sectional view illustrating another example of aneighborhood of a connection terminal portion in the display device 10according to the present invention. As illustrated in FIG. 5B, theconnection terminal 450 of the touch sensor 400 and the connectionterminal 250 of the organic EL element layer 200 are connected to acommon flexible printed circuit board (FPC) 800.

As described above, the connection terminal 450 of the touch sensor 400and the connection terminal 250 of the organic EL element layer 200 areconnected to one flexible printed circuit board (FPC) 800, hereby beingcapable of simplifying the connecting process, and reducing the members.As a result, a reduction in the manufacture cost is realized.

FIG. 6A is a plan view schematically illustrating an arrangement ofdetection electrodes included in an organic electroluminescent devicewith a touch sensor 10 according to another embodiment of the presentinvention. FIG. 6B is a schematic cross-sectional view of a neighborhoodof a part taken along a line VI-VI in FIG. 6A. FIG. 6B is across-sectional view illustrating another example of a neighborhood ofthe connection terminal portion in the organic electroluminescent devicewith a touch sensor 10 according to the present invention.

As illustrated in FIG. 6B, the first detection electrodes 410 and thesecond detection electrodes 420 which configure the touch sensor 400 areelectrically connected to lead lines connected to the connectionterminal 450 disposed on the first substrate 100, through a contact hole460 formed in ends of those detection electrodes.

With the application of the above structure, the connection terminal 450of the touch sensor 400 and the connection terminal 250 of the organicEL element layer 200 are formed in the same plane of the first substrate200. For that reason, the electric connection with the external circuitis further facilitated.

Also, the organic electroluminescent device with a touch sensorconnected to the contact hole 460 as described above fulfills a requestfor thinning, and has the effect of facilitating the electric connectionwith the external circuit.

Second Embodiment

Hereinafter, a description will be given an embodiment in which even ifa higher-definition organic electroluminescent display unit is appliedto the organic electroluminescent device with a touch sensor 10, thedisconnection of the detection electrodes configuring the touch sensoris suppressed while thinning the device.

An organic electroluminescent device with a touch sensor 10 according toa second embodiment of the present invention is different from theorganic electroluminescent device with a touch sensor 10 according tothe first embodiment in that the first sealing film 300 is configured bythe first sealing film 300 and a first planarizing layer 310.

FIG. 4B is a cross-sectional view of the organic electroluminescentdevice with a touch sensor 10 according to the second embodiment of thepresent invention. As illustrated in FIG. 4B, the first sealing film 300of the organic electroluminescent device with a touch sensor 10according to the second embodiment has the first planarizing layer 310that is formed on the second substrate side of the first sealing film300, and flattens the unevenness of the surface.

In this example, the first planarizing layer 310 is made of an organicmaterial. The first planarizing layer 310 is provided for the purposesof planarizing the unevenness of a surface of a side of the firstsealing film 300 where the first detection electrodes 410 is disposed,and reducing an influence of a capacitance formed between the firstplanarizing layer 310 and the cathode 230. Therefore, the thickness ofthe first planarizing layer 310 may be appropriately selected. Whenvarnish (liquid material in which organic resin is dissolved in asolvent) of organic resin is coated on an uneven surface whereby thevarnish preferentially flows into a concave portion to effectivelyflatten the unevenness of the surface of the first sealing film 300.

Also, the first planarizing layer 310 may be made of, for example, anorganic resin. The organic resin applied to the first planarizing layer310 may be selected from a group consisting of, for example, acrylic,polyimide, epoxy, and an optically clear adhesive (OCA). Apart from themethod of coating the organic material, the organic material may beformed by a low-temperature vapor deposition method or a resin sheetsticking method. Also, the first planarizing layer 310 may be graduallythinned toward the outside from the display surface 30, and the firstsealing film 300 may come in contact with the second sealing film 500 onthe outermost portion. With this configuration, the penetration ofmoisture from the external can be effectively prevented.

Also, the first planarizing layer 310 may have a thickness of 1 to 100μm. It is preferable to set the first planarizing layer 310 to 10 μm orhigher because the effect of suppressing the disconnection of the touchsensor is enhanced, and an influence of the capacitance between thecathode 230 and the touch sensor 400 can be reduced. Also, although anupper limit of the thickness of the first planarizing layer 310 is notparticularly defined, because an increase in the thickness of the firstplanarizing layer 310 is disadvantageous to thinning, the upper limit ofthe thickness may be set to, for example, be equal to or lower than 80μm, or lower than 80 μm.

The material and the forming method of the first planarizing layer 310are not limited to those described above.

As compared with the organic electroluminescent device having no touchsensor, the organic electroluminescent device with a touch sensoraccording to the second embodiment as described above can be realized byonly an increase in the thickness of the first and second detectionelectrodes substantially configuring the touch sensor, and the thicknessof the first planarizing layer, and fulfills the request for thinning.Also, the organic electroluminescent device with a touch sensoraccording to the second embodiment has the effect of suppressing thedisconnection of the touch sensor, and also the effect of enhancing thereliability of the device.

Also, the organic electroluminescent device with a touch sensoraccording to the second embodiment as described above may employ theconnection structure of the connection terminal described in the organicelectroluminescent device with a touch sensor according to the firstembodiment.

Also, the second sealing film 500 may have a second planarizing layer(not shown) that flattens the unevenness of the surface in an area whereat least the second detection electrode 420 is arranged, on a sidefacing the second substrate 600.

Also, when the second sealing film 500 has the second planarizing layer,the second planarizing layer may be made of, for example, an organicresin. Because the second planarizing layer is provided for the purposeof planarizing the unevenness of the surface, there is no need to selectany material taking water permeability and air permeability, which arefunctions of the second flattering layer, into account. Also, whenvarnish (liquid material in which organic resin is dissolved in asolvent) of organic resin is coated on an uneven surface whereby thevarnish preferentially flows into a concave portion with the result thatthe unevenness of the surface of the second sealing film 500 can beeffectively flattened, which is preferable.

The material and the forming method of the second planarizing layer arenot limited to those described above.

Also, the second planarizing layer may have a thickness of 1 to 100 μm.It is preferable to set the second planarizing layer to 10 μm or higherbecause the effect of suppressing the disconnection of the touch sensoris enhanced. Also, although an upper limit of the thickness of thesecond planarizing layer is not particularly defined, because anincrease in the thickness of the second planarizing layer isdisadvantageous to thinning, the upper limit of the thickness may be setto, for example, be equal to or lower than 80 μm, or lower than 80 μm.

While there have been described what are at present considered to becertain embodiments of the invention, it will be understood that variousmodifications may be made thereto, and it is intended that the appendedclaim cover all such modifications as fall within the true spirit andscope of the invention.

What is claimed is:
 1. A display device comprising: a first substratehaving an insulating surface; a display region having a plurality ofpixels on the insulating surface, each of the plurality of pixels havinga display element; a first sealing layer covering the display region; apair of detection electrodes on the first sealing layer; and a pluralityof terminals outside the display region on the first substrate, wherein.one of the pair of detection electrodes is connected to one of theplurality of terminals via a contact hole formed in the first sealinglayer.
 2. The display device according to claim 1, wherein the pair ofdetection electrodes have a first detection electrode layer and a seconddetection electrode layer, each of the first detection electrode layerand the second detection electrode layer has a protruding surface at anopposite side from the first sealing layer, a second sealing layer isbetween the first detection electrode layer and the second detectionelectrode layer, and the second sealing layer is in contact with theprotruding surface of the first detection electrode layer.
 3. Thedisplay device according to claim 2, further comprising a third sealinglayer, wherein the third sealing layer is in contact with the protrudingsurface of the second detection electrode layer.
 4. The display deviceaccording to claim 3, wherein the third sealing layer covers a regionabove the contact hole.
 5. The display device according to claim 1,further comprising a third sealing layer, wherein the third sealinglayer covers a region above the contact hole.
 6. The display deviceaccording to claim 1, wherein the display element includes an anode, acathode, and an EL layer between the anode and the cathode, the cathodeis commonly formed across the plurality of pixels, and the cathode isentirely in contact with the first sealing layer.